Creating the Wildlife-Friendly Fence

FWP provides instruction on how to modify fencing to prevent elk, deer, and pronghorn from injuring themselves and damaging private property. By Christine Paige

This story is featured in Montana Outdoors July–August 2009

While Steve Primm was driving through the Madison Valley south of Ennis one recent fall, a flash of white caught his eye. Primm, who lives nearby, had seen a pronghorn buck zigzagging next to a fence in a way that made him pause. He pulled onto a side road and found the antelope wrapped in barbed wire. Using his fence cutters, he snipped a wire near the buck’s hind leg. “That’s all it took,” Primm says. “He thrashed a bit, freed himself, and ran away.

Other wild animals often are not so lucky. Elk, deer, pronghorn, and other large mammals are injured or killed in Montana each year running into fences or entangling themselves in wire. And landowners face costly and time-consuming repairs fixing barbed wire and woven-wire (4- to 6-inch-square mesh) fences damaged by wildlife. A new booklet by Montana Fish, Wildlife & Parks offers livestock growers and others practical solutions for modifying fences at problem sites to help wildlife while saving money in fence repairs.

Entangled and blocked
Large ungulates such as deer, elk, moose, mountain sheep, and pronghorn are capable of jumping fences, but they occasionally get caught in barbed wire. “Often the top strand is too high,” says Craig Jourdonnais, FWP wildlife biologist for the Bitterroot Valley. “The problem is compounded in late winter, when elk and deer are at their weakest and become more vulnerable to being caught in the wires.”
Fences also obstruct daily and seasonal movements of wildlife. Woven-wire fences often block fawns and calves from following adult deer and elk able to jump over the barriers. Woven wire also obstructs animals such as bears and bobcats unable to leap fences and too large to slip through the mesh. Fences pose particular problems for pronghorn. Although capable of leaping over a fence, pronghorn usually crawl under. Woven-wire fences can completely block pronghorn movement.

Sensible solutions
Most fences don’t cause problems for wildlife. But some sections, especially where wildlife regularly move daily or seasonally, can benefit from minor modifications. Recently FWP produced a 41-page booklet, “A Landowner’s Guide to Wildlife Friendly Fences: How to Build Fence with Wildlife in Mind,” that offers sensible solutions. With photographs and detailed illustrations, the booklet explains how to modify fences in trouble spots to contain livestock while still allowing wildlife to move freely through important habitats, such as gullies, ridges, wetlands, and streams. Examples:

Lower the top strand of barbed wire and raise the bottom wire.

Replace the top barbed wire with a smooth wire or rail.

Modify sections of fence so a top rail or wire can be temporarily lowered at deer, elk, and moose trails during seasonal migrations, and a bottom wire can be raised so calves, fawns, or pronghorn can slip underneath.

Replace the top strand with highly visible white poly-wire or attach short pieces of white vinyl “undersill” siding strips (available at most home improvement centers) to fence wires in areas where wildlife collisions or entanglements are common.

Electric fencing is another way to keep livestock in place while allowing wildlife to move freely. Juanita Vero, the fifth-generation owner and manager of the E Bar L guest ranch in the Blackfoot Valley, has fixed her share of damaged fence. On the ranch, 80 head of horses share 4,000 acres of range with large numbers of deer and elk. One half-mile section of the ranch’s traditional barbed wire fence required frequent maintenance where it crossed a route that elk used daily. The large animals often stretched and collapsed wires as they lumbered over the fence. The Vero family sought help from the local FWP wildlife biologist, Jay Kolbe.

Under an agreement in which Kolbe evaluated the fence design at the trouble spot and FWP split costs and labor with the ranch, department crews and the Veros built a two-wire electrified fence, spaced between timber and fiberglass posts. The top wire is a high-visibility electric wire. The lower wire, hung several inches below the top one, is standard 12.5-gauge high-tensile steel that conducts no current. While the fence contains horses, elk easily pass over or underneath. “When nobody is putting pressure on them, even the big bulls go under with no problem” says Vero.

Elsewhere on the ranch, the family has successfully placed temporary single-strand electric fencing to divide pastures into smaller units. That allows them to control where horses graze, allows wildlife of all types to pass freely, and eliminates fence repair.

Ultimately, any fence must be functional and meet a landowner’s needs. Many prop­erty damage problems and wildlife injuries can be prevented with modifications on only a short section of fence. By installing wildlife-friendly fencing, a landowner helps Mon­tana’s elk, deer, pronghorn, and other wild animals move freely across the landscape without doing damage to fences—
or themselves.

Christine Paige is an independent wildlife biologist and science writer who lives in
the Bitterroot Valley. Additional research contributed by Bryce Andrews.